Demineralisation of bone is caused by the phagocytosis of  

Options

A. neutrophils
B. eosinophils
C. osteoclasts
D. osteoblasts

Answer

**Step-by-Step Solution:**

1. **Understanding Bone Cells**: To answer the question, we first need to understand the different types of cells involved in bone metabolism. There are two main types of bone cells: osteoblasts and osteoclasts. Osteoblasts are responsible for bone formation, while osteoclasts are involved in bone resorption.

2. **Identifying the Function of Osteoclasts**: Osteoclasts are specialized cells that break down bone tissue. They do this through a process called phagocytosis, where they engulf and digest bone matrix components, leading to the demineralization of bone.

3. **Differentiating Between Cell Types**: The question provides several options: neutrophils, eosinophils, osteoclasts, and osteoblasts. Neutrophils and eosinophils are types of white blood cells (WBCs) that primarily deal with pathogens and immune responses, not bone metabolism.

4. **Confirming the Correct Answer**: Since osteoclasts are the cells that perform the demineralization of bone through phagocytosis, they are the correct answer. Osteoblasts, on the other hand, are responsible for building bone and do not participate in demineralization.

5. **Conclusion**: Therefore, the demineralization of bone is caused by the phagocytosis of osteoclasts.

**Final Answer**: The demineralisation of bone is caused by the phagocytosis of **osteoclasts**.

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